Depression and insomnia often go hand-in-hand. Mendoza & Company, a national pharmaceutical firm, has positioned itself...

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Depression and insomnia often go hand-in-hand. Mendoza & Company, a national pharmaceutical firm, has positioned itself as a specialist in the production of both antidepressants and sleeping pills. Mendoza's current business model describes the following breakdown of America's approximately 50 million adults suffering from insomnia: 17% use both antidepressants and sleeping pills regularly, 24% use only antidepressants regularly, 15% use only sleeping pills regularly, and the remaining 44% use neither antidepressants nor sleeping pills regularly. In a recent study on insomnia in a psychiatry journal, 180 American adults suffering from insomnia (but otherwise chosen at random) were asked about their use of antidepressants and sleeping pills. The breakdown of their answers is given by the top row of numbers in the table below. (These numbers are the frequencies observed for the sample of 180 insomniacs.) The second row of numbers gives the expected frequencies under the hypothesis that Mendoza's model is correct. The bottom row of numbers contains the following value for each of the categories of medication use. (fo-f) (Observed frequency - Expected frequency) JE Expected frequency Espaol ? Part 1 Fill in the missing values in the table. Round your responses for the expected frequencies to two or more decimal places. Round your to three or more decimal places. Send data to Excel Both Only antidepressants Only sleeping pills Neither Total Observed frequency 40 34 22 22 84 180 Expected frequency 43.20 27.00 JE 2 (Jo-Jz) JE U 1.959 0.926 U (Jo-JE) responses Part 2 Answer the following to summarize the test of the hypothesis that Mendoza's model is correct. Use the 0.05 level of significance for the test. (a) Determine the type of test statistic to use. Type of test statistic: Chi-square Degrees of freedom: (b) Find the value of the test statistic. (Round your answer to two or more decimal places.) (c) Find the critical value. (Round your answer to two or more decimal places.) (d) Can we conclude that the percentages given in Mendoza's model are incorrect? O Yes No Depression and insomnia often go hand-in-hand. Mendoza & Company, a national pharmaceutical firm, has positioned itself as a specialist in the production of both antidepressants and sleeping pills. Mendoza's current business model describes the following breakdown of America's approximately 50 million adults suffering from insomnia: 17% use both antidepressants and sleeping pills regularly, 24% use only antidepressants regularly, 15% use only sleeping pills regularly, and the remaining 44% use neither antidepressants nor sleeping pills regularly. In a recent study on insomnia in a psychiatry journal, 180 American adults suffering from insomnia (but otherwise chosen at random) were asked about their use of antidepressants and sleeping pills. The breakdown of their answers is given by the top row of numbers in the table below. (These numbers are the frequencies observed for the sample of 180 insomniacs.) The second row of numbers gives the expected frequencies under the hypothesis that Mendoza's model is correct. The bottom row of numbers contains the following value for each of the categories of medication use. (fo-f) (Observed frequency - Expected frequency) JE Expected frequency Espaol ? Part 1 Fill in the missing values in the table. Round your responses for the expected frequencies to two or more decimal places. Round your to three or more decimal places. Send data to Excel Both Only antidepressants Only sleeping pills Neither Total Observed frequency 40 34 22 22 84 180 Expected frequency 43.20 27.00 JE 2 (Jo-Jz) JE U 1.959 0.926 U (Jo-JE) responses Part 2 Answer the following to summarize the test of the hypothesis that Mendoza's model is correct. Use the 0.05 level of significance for the test. (a) Determine the type of test statistic to use. Type of test statistic: Chi-square Degrees of freedom: (b) Find the value of the test statistic. (Round your answer to two or more decimal places.) (c) Find the critical value. (Round your answer to two or more decimal places.) (d) Can we conclude that the percentages given in Mendoza's model are incorrect? O Yes No